This invention relates to plasma etching and polymer formation.
Equal proportions of oxidizing and reducing species are produced by supplying a plasma with carbon tetrafluoride, and the etch rate of silicon in such a plasma is typically found to be of the order of forty five times that of its oxide and twenty times that of its nitride. In semiconductor device manufacture many etching applications exist, such as in silicon planar technology, wherein a reduced, or preferably a reversed, etch rate ratio is desired.